... ) Supply warm and clean air for the chicken or pig house 3) Coal as fuel Name:9RFL-20D Air HeaterScope: Used in livestock ... of furnace, air inlet, air outlet, furnace gate, ventilator, air blower, chimney.Features:1. It has the advantages of rapid providing of clean hot air efficiently;2 ... of burn-resistance, wide longevity, automatic and manual temperature control. Coal-fired Air Heater 9RFL-20D